Advice on Isolator

[SUNRAY]

We are soon to upgrade to 3 phase supply for a church hall, meter fitting company have stated they will provide all new tails and install an isolator if we provide it (onto the existing 1ph tails).
In the church is one of these or something very much like it:
https://www.ebay.co.uk/itm/wylex-4-...797429?hash=item36338830f5:g:uggAAOSwvfZaOjKA
The Churches approved electrician, who will ultimately rearrange the existing tails to 5 CU's, is happy for a similar device to be fitted and it will fit nicely in the space.

Elsewhere I'm seeing similar devices being replaced with big metal boxes, any views on suitability or longevity are welcome.

 

[EFLImpudence]

I expect that's more to do with the non-combustible requirement - whether it applies or not.

 

[JohnW2]

In the church is one of these or something very much like it:
https://www.ebay.co.uk/itm/wylex-4-...797429?hash=item36338830f5:g:uggAAOSwvfZaOjKA
The Churches approved electrician, who will ultimately rearrange the existing tails to 5 CU's, is happy for a similar device to be fitted and it will fit nicely in the space. Elsewhere I'm seeing similar devices being replaced with big metal boxes, any views on suitability or longevity are welcome.

I don't know about non-domestic environments, but isolators like that are being routinely installed by suppliers in domestic premises ... like mine (they provided it, so couldn't afford MK ) ...

I would have thought that the only reason for favouring a 'big metal box' would be if the environment were such that one wanted the added mechanical robustness. Provided it was rated adequately (you don't mention the currents of the supply), I can't see why a 'plastic' one would not be 'suitable', and I wouldn't really think that 'longevity' would be an issue for a main isolator, which presumably will very rarely be operated.

Kind Regards, John

 

[ban-all-sheds]

I don't know about non-domestic environments, but isolators like that are being routinely installed by suppliers in domestic premises

"Are", or "were"?

Hard to argue, IMO, that an isolator like that is not "similar switchgear".

It would be interesting to know if suppliers were still installing plastic-housed isolators, and if they had ever been challenged. Or, conversely, if any have ever refused to install a customer-supplied plastic one.

 

[SUNRAY]

I don't know about non-domestic environments, but isolators like that are being routinely installed by suppliers in domestic premises ... like mine (they provided it, so couldn't afford MK ) ...
View attachment 143635

I would have thought that the only reason for favouring a 'big metal box' would be if the environment were such that one wanted the added mechanical robustness. Provided it was rated adequately (you don't mention the currents of the supply), I can't see why a 'plastic' one would not be 'suitable', and I wouldn't really think that 'longevity' would be an issue for a main isolator, which presumably will very rarely be operated.

Kind Regards, John

By longevity I was thinking about 'non combustible regs' changing rather than mechanical failure, after all it is identical to the main switch in the CU.



This is more the reason for starting this thread.

I expect that's more to do with the non-combustible requirement - whether it applies or not.

"Are", or "were"?

It would be interesting to know if suppliers were still installing plastic-housed isolators, and if they had ever been challenged. Or, conversely, if any have ever refused to install a customer-supplied plastic one.

I'm perfectly happy with plastic, and as this is 'non residential' and the 5 existing CU's are plastic...

 

[ban-all-sheds]

Are you doing this sort of thing on purpose?

My reply was to JW2 about domestic isolators - nothing to do with your situation.

 

[JohnW2]

By longevity I was thinking about 'non combustible regs' changing rather than mechanical failure, after all it is identical to the main switch in the CU. .... This is more the reason for starting this thread.I'm perfectly happy with plastic, and as this is 'non residential' and the 5 existing CU's are plastic...

Ah. I was typing my post when EFLI posted his!

However, I had considered this. Whilst I agree with BAS that it's hard not to regard such an isolator as "similar switchgear", it is also hard to regard a church hall as a "domestic (household) premises" - so I assumed that there is (currently) no non-combustible' requirement.

Is your concern that the ' non-combustible' requirement might eventually extend to non-domestic premises?

Edit: I forgot to say ... as for BAS's question about the practice of electricity suppliers, my ('plastic') isolator (as pictured above) was supplied and installed (by E.ON) on 9th January 2017, over a year after the 'con-combustible' reg came into force.

Kind Regards, John

 

[ban-all-sheds]

it is also hard to regard a church hall as a "domestic (household) premises" - so I assumed that there is (currently) no non-combustible' requirement.

It is, and there isn't. Unless it adjoins accommodation for the verger?

Elsewhere I'm seeing similar devices being replaced with big metal boxes, any views on suitability or longevity are welcome.

I expect that's more to do with the non-combustible requirement - whether it applies or not.

I think what EFLI said was reasonable - we don't know where "elsewhere" is, it could easily include domestic premises, there could well be people installing metal isolators because they mistakenly think the requirement applies, or because they judge that it does in a possibly grey area (e.g. a CU behind a pub bar and the publican lives on the premises). And a business which stocks isolators might well standardise on metal ones to save costs, as it is OK to install them where they are not required to be metal.

Edit: I forgot to say ... as for BAS's question about the practice of electricity suppliers, my ('plastic') isolator (as pictured above) was supplied and installed (by E.ON) on 9th January 2017, over a year after the 'con-combustible' reg came into force.

If you get a bit of slack time, it would be interesting to see what happens if you "innocently" contact them to ask why they did that.

 

[JohnW2]

No way will I ask them, 'innocently' or otherwise, since they might decide to 'upgrade' it to a metal one! - and, unless there are 'Class 2' isolators around, I still don't really understand how a metal one can be installed safely in a TT installation (and I have similar concerns about a metal CU with TT).

 

[ban-all-sheds]

Fair point.

 

[SUNRAY]

Are you doing this sort of thing on purpose?

My reply was to JW2 about domestic isolators - nothing to do with your situation.

If this was aimed at me, perhaps I need to clarify my reason for starting the thread and my comment in #5.

The DNO and meter fitting division (possibly a different company) have visited site and confirmed a 3ph supply is present in the cutout and we can upgraded to a 3ph supply FOC, however they are not prepared to rearrange the existing 5 sets of tails (as predicted) and their suggestion is for us to supply an isolator which they are prepared to install where the Henly blocks are currently located and terminate the existing 1ph tails as a stop gap.

As it is the drama group (me) who have instigated this upgrade (after reaching a peak of 92A during the course of a show on the current 80A fuse) it is they who are expected to cover any cost implication. Any electrical work will be done by the churches regular electrician and he has suggested an isolator similar to that fitted in the church. I am in agreement and would prefer a plastic enclosure but wonder about any future 'non combustible' implication. Hence this thread for others opinions.

My comment in #5 highlights EFL's and BAS's posts as the reason I started the thread, I realise where BAS's question is aimed but believed the sentiment is pertinent to my case. If I have misunderstood or misconstrued the intent then I apologise.

Please not another slanging match where posts are saying the same thing.

 

[ban-all-sheds]

1. - Unless the supply is TT there is no good reason to prefer a plastic enclosure, unless they are significantly cheaper.
2. - No future "non combustible" requirements would mean you were forced to replace a plastic one with a metal one.

 

[SUNRAY]

1. - Unless the supply is TT there is no good reason to prefer a plastic enclosure, unless they are significantly cheaper.
2. - No future "non combustible" requirements would mean you were forced to replace a plastic one with a metal one.

I have seen far too many bad results of attempting to do something live 'because I didn't want to break the seal'. Silly idea, I know but...

 

[ban-all-sheds]

Please explain what that has to with whether the seals were on a plastic enclosure or a metal one.

 

[Risteard]

Hard to argue, IMO, that an isolator like that is not "similar switchgear".

What are you talking about?

It is very plainly and obviously not a "similar switchgear assembly" to a type-tested DBO as it contains no overcurrent protection. It is simply a multipole switch.